an insincere or forced smile/laugh used to smooth a situation or be polite; a polite/ingratiating smile.
上司の冗談に対して、仕方なく愛想笑いを浮かべた。
I couldn't help but give a forced smile at my boss's joke.
初対面でぎこちない会話が続き、つい愛想笑いをしてしまった。
The awkward conversation with someone I just met continued, and I ended up giving a polite smile.
本音を言えずに愛想笑いばかりするのは疲れる。
It's tiring to keep giving polite smiles without saying what you really think.
あの場では愛想笑いでやり過ごすのが最善だと思った。
I thought it was best to get through that situation with a polite smile.